BANCROFT 
LIBRARY 

o- 

THE  LIBRARY 

OF 

THE  UNIVERSITY 
OF  CALIFORNIA 


DEPARTMENT  OF  THE 

UNITED    STATES    GEOLOGICAL    SUE 
J.  W.  POWELL   DIRECTOR 


IODINE 


BY 


T. 


ABSTRACT   FROM    ''MINERAL    RESOURCES    OF   THE    UNITED    STATES, 

CALENDAR  YEARS  1883  AND  1884  "-ALBERT  WILLIAMS,  JR., 

CHIEF  OF  DIVISION  OF  MINING  STATISTICS 


WASHINGTON 

GOVERNMENT    PRINTING    OFFICE 

1885 


DEPARTMENT  OF  THE  Iff JSBIOB 

UNITED    STATES    GEOLOGICAL    SURVEY 
J.  W.  POWELL   DIRECTOR 


IODINE^ 


BY 


IDT.  ,13  A. 


ABSTRACT   FROM    "MINERAL    RESOURCES    OF   THE    UNITED   STATES, 
CALENDAR  YEARS  1883  AND  1884"— ALBERT  WILLIAMS,  JR., 
CHIEF  C/  DIVISION  OF  MINING  STATISTICS      • 


WASHINGTON 

GOVERNMENT    PRINTING    OFFICE 

1885 


IODINE. 

BY  DAVID  T.  DAY. 

Domestic  occurrences. — Traces  of  iodides  have  been  found,  together 
with  chlorides  and  bromides,  in  the  various  salt  wells,  particularly  those 
of  the  West  Virginia  and  Ohio  district.  At  Saratoga,  New  York,  traces 
have  been  detected,  but  although  the  percentage  of  iodine  in  profitable 
sources  is  extremely  small,  the  occurrences  in  the  United  States  will, 
in  all  probability,  remain  entirely  insignificant.  Although  iodine  is  not 
produced  in  the  United  States,  its  important  influence  upon  the  bromine 
industry,  in  which  the  United  States  holds  first  rank,  makes  a  considera- 
tion of  the  peculiar  features  of  the  iodine  industry  advisable. 

Sources  and  mode  of  manufacture. — Sea  water  and  the  South  American 
nitrate  deposits  have  served  as  the  only  sources  of  iodine.  The  minute 
trace  of  iodine  in  the  former  is  concentrated  by  many  varieties  of  algae, 
so  that  these  plants  when  perfectly  dry  contain  from  0.0297  to  0.4535 
per  cent,  of  their  weight  in  iodine,  in  the  form  of  iodides  of  the  alkali 
metals  (Stanford).  Before  the  discovery  of  iodine  by  Courtois,  in  1811, 
these  alga3  were  collected  on  the  shores  of  Ireland,  Scotland,  and  Nor- 
mandy, and  their  ashes  ( "kelp,"  u  varec " )  furnished  a  considerable  part 
of  the  soda  and  potash  of  that  time.  According  to  the  report  of  Mr. 
E.  0.  Stanford  (a)  the  production  of  kelp,  that  is,  the  ashes  of  several 
varities  of  seaweed,  amounted  to  20,000  tons  from  the  western  islands 
alone  at  the  beginning  of  this  century,  and  sold  for  £20  to  £22  per  ton. 
The  importation  of  barilla  then  began,  and  this,  together  with  the 
establishment  of  the  Leblanc  soda  process,  reduced  the  price  of  kelp  to 
£10  per  ton.  Among  the  manufacturers  of  sodium  salts  from  kelp  was 
Courtois,  in  Paris.  His  discovery  of  iodine  in  the  kelp  was  made  at  a 
time  when  theoretical  discussions  as  to  the  elementary  character  of 
chlorine  subjected  the  properties  of  that  substance  to  careful  study, 
and  the  analogous  character  of  iodine  led  in  an  unusally  short  time  to 
a  general  knowledge  of  this  element  and  its  possible  uses.  It  was  ex- 
tracted from  kelp  during  the  preparation  of  soda;  but  small  quantities 
fully  satisfied  the  demand,  so  that  its  source  was  no  more  valuable  than 
before  iodine  was  discovered.  In  fact  the  price  of  kelp  sank  gradually 
to  £2  per  ton  in  1831.  Between  1841  and  1844,  however,  iodine  was 
applied  to  the  manufacture  of  aniline  dyes.  In  1845  the  production  of 
iodine  began  on  a  commercial  scale,  and  kelp  was  again  in  demand. 

a  Chemical  News,  Vol.  35,  page  172,  1877. 


IOBINE. 


855   • 


The  imports  to  the  Clyde  increased  from  2,565  tons  in  1841  to  6,000  tons  "" 
in  1845.  In  the  latter  year  there  were  four  small  works  engaged  in  the 
manufacture  of  iodine  j  in  1846  this  number  increased  to  twenty.  The 
kelp  required  was  not  the  same ;  formerly  that  yielding  most  soda  was 
needed,  but  this  was  poorest  in  iodides,  which  now  became  the  im- 
portant constituents.  Moreover,  it  was  foui^d  that  kelp  richest  in 
iodine  was  also  richest  in  potassium,  which  also  was  valuable ;  potas- 
sium chloride  being  worth  £25  per  ton.  The  following  table  gives  the 
imports  of  kelp  into  the  Clyde  for  thirty-five  years,  and  also  the  price 
of  iodine  from  the  time  of  its  industrial  application  up  to  the  present. 
The  earlier  figures  have  been  compiled  by  Mr.  Stanford,  of  Glasgow, 
and  the  later  prices  of  iodine  have  been  furnished  through  the  kindness 
of  Messrs.  Powers  &  Weightman,  of  Philadelphia. 

Kelp  imports  into  the  Clyde,  and  price  of  iodine. 


Years  ending  June  30— 

Kelp  im- 
ports.    • 

Price  of 
iodine. 

Years  ending  June  30— 

Kelp  im- 
ports. 

Price  of 
iodine. 

1841 

Long  tons. 
2  5^ 

Per  pound. 
$1.20  ' 

1865 

Long  tons. 
13  741 

Jr&f  pound. 
$1  84 

1842  

1,  887 

1.12 

1866  

8  858 

2.40 

1813                          ..     .. 

1,965 

1.44 

1867 

8  174 

2  88 

1844  

3,263 

2.88  ! 

1868  

8,116 

3.04 

1845 

6  0;sG 

7.46 

1869 

8  978 

3  12 

1846  

3,627 

5.34 

1870  

9,257 

3.04 

1847    .... 

4  000 

2.64 

1871 

9  384 

3  44 

1848 

4  400 

2  64 

1872 

10  049 

8  If) 

1849    

4  731 

2.64 

1873 

9  449 

5  12 

1850  

11,421 

2.56 

1874 

10  923 

a3.  52 

1851  
1852  

7,320 
5,418 

2.08 
3.64 

1875 

8  643 

62.94 
a2  44 

1853  
1854  

6,491 
4,679 

3.72 

2.88 

1876 

62.25 
al.92 

1855  

1856 

5,826 
6  349 

3.20 
3  28 

1877 

61.87 
c3  28 

1857  

8,641 

2.96 

1878 

c4  00 

1858 

8  123 

2.52 

1879 

c4  48 

1859  

8,190 

2.32 

1880 

d\  92 

1860 

7  754 

2.04 

1881 

d2  00 

1861  

9,722 

1.68 

1882      . 

dl  60 

1862 

9  414 

1  36 

1883 

dl  28 

1863  

14,  018 

1.20 

1884 

di;20 

1864  

11,349 

2.00 

e2.  88 

a  Scotch.        &  Peruvian.        c  Combination.        d  Combination  broken.       e  Recombination. 

The  extraordinary  fluctuations  in  the  price  of  iodine  serve  to  indi- 
cate the  complicated  conditions  of  oversupply,  extended  production, 
combination  of  manufacturers,  and  open  competition,  to  which  an  in- 
dustry is  occasionally  subjected.  During  the  early  years  of  the  manu- 
facture the  extended  use  of  iodine,  principally  in  the  production  of  ani- 
line dyes,  caused  sudden  fluctuations  in  its  price,  while  the  price  of  the 
raw  material  remained  practically  unchanged.  This  involved  many 
manufacturers  in  heavy  losses,  the  profits  under  high  prices  usually 
falling  to  speculators,  while  the  manufacturer  was  left  to  sustain  the 
industry  when  prices  were  low.  For  this  reason  the  number  of  manu- 
facturers in  Glasgow  was  reduced  during  1873-1877  to  about  three, 
producing  in  all  from  50  to  60  tons  of  iodine  from  about  10.000  tons  of 


856  MINERAL   RESOURCES. 

kelp.    The  production  in  Trance  at  this  time  was  somewhat  less,  amount 
ing  to  40  tons,  derived  from  16,000  tons  of  inferior  "  varec  "  or  kelp. 

As  early  as  1885  the  presence  of  sodium  iodate  was  noticed  in  the 
South  American  caliche  (native  sodium  nitrate).  The  effort  was  made 
by  Thiercelin  to  extract  the  iodine  from  the  mother  liquors  from  sodium 
nitrate  by  precipitating  the  iodine  by  means  of  acid  sodium  sulphite, 
or,  better,  sodium  nitrite,  prepared  by  fusing  the  domestic  sodium  ni- 
trate with  one  fifth  its  weight  of  charcoal.  But  the  difficulty  of  drying 
the  iodine  thus  obtained  by  spreading  on  porous  plates,  and  the  fact 
that  frequently  the  greater  part  of  the  iodine  existed  as  sodium  iodide 
and  escaped  precipitation,  prevented  active  competition  with  European 
iodine  until  Langbcin's  method  was  introduced  in  the  province  of  Tara- 
paca,  then  belonging  to  Peru,  but  at  present  held  by  Chili.  By  this 
method  the  mother  liquors  were  treated  with  an  excess  of  sodium  sul- 
phite or  acid  sodium  sulphite,  converting  the  iodate  into  hydriodic  acid, 
from  which  cuprous  iodide  was  precipitated  by  copper  sulphate  and 
sodium  sulphite.  In  1874  South  American  iodine  was  offered  upon  the 
London  market  for  10J  to  11  pence  per  ounce,  against  13  pence  for 
Scotch  iodine.  The  result  was  an  active  competition,  soon  resolving 
into  commercial  warfare,  which  has  exerted  great  influence  upon  the 
industry.  All  through  1874  Peruvian  iodine  was  offered  at  prices 
about  20  per  cent,  btlow  the  Scotch  product.  At  the  beginning  of 
1875  both  varieties  sold  for  two-thirds  the  price  of  1873,  and  the  Pe- 
ruvian iodine  still  led  the  way  to  lower^  prices,  until  at  the  close 
of  1876  the  price  had  fallen  to  5f  pence  per  ounce,  and  both  sides 
were  ready  to  compromise  or  else  give  up  the  manufacture,  which 
now  yielded  little  profit  to  either.  In  order  to  keep  up  the  com- 
petition the  European  method  of  producing  iodine  had  undergone  a 
revolution.  Formerly  the  custom  was  to  allow  seaweed  to  collect 
during  the  winter  months.  It  lay  exposed  upon  the  coasts  until  some- 
times 90  per  cent,  of  the  iodine  had  been  washed  away  from  the 
partially  decomposed  weed,  before  it  was  burned  and  shipped  to  Glas- 
gow. Further,  the  weed  was  burned  in  long  kilns  made  of  loose 
stone  walls  and  turf;  the  burning  seaweed  here  attained  a  very  high 
temperature.  This  part  of  the  work  was  done  by  women  and  children ; 
the  men  then  raked  the  ash  with  iron  "  clats"  until  it  formed  a  molten 
slag.  "  During  this  laborious  process,"  says  Stanford,  (i  more  than  50 
per  cent,  of  the  iodine  is  often  wasted,  and  a  large  amount  of  potash; 
indeed,  so  intense  is  the  heat  that  sufficient  soda  is  volatilized  to  give 
an  intense  monochromatic  flame.  The  high  temperature  also  enables 
the  carbon  to  deoxidize  the  alkaline  sulphates  to  sulphides  and  other 
sulphur  compounds ;  these  become  concentrated  in  the  mother  liquor, 
and  entail  a  large  expenditure  of  oil  of  vitriol,  and  give  rise  to  great 
nuisance  in  the  lixiviation."  The  first  improvement,  proposed  in  1862, 
was  to  subject  the  kelp  to  destructive  distillation  in  closed  vessels,  by 
which  ammonia,  acetic  acid,  naphtha,  a  considerable  amount  of  illuminat- 


IODINE. 


857 


ing  gas,  and  finally  a  variety  of  charcoal  better  than  others  for  decolor- 
izing, etc.,  were  obtained.  From  this  charcoal  twice  as  much  iodine 
was  obtained  as  from  the  kelp.  This  radical  improvement  was  only 
used  on  the  islands  of  Tyree  and  North  Uist  until  the  competition  with 
Peru.  The  next  improvement,  proposed  by  Pellieux  and  Maze"-Launay, 
consists  in  drying  the  fresh  seaweed  for  four  or  five  days,  then  allowing 
it  to  ferment  until  decomposition  begins.  'The  object  of  the  fermenta- 
tion is  to  bring  the  seaweed  into  a  condition  in  which  no  iodine  will 
be  lost  in  burning.  The  sulphur  compounds  in  the  algae  are  converted 
into  alkaline  sulphides;  these  decompose  the  organic  iodine  compounds 
into  alkaline  iodides,  which  are  not  so  easily  volatilized.  The  water 
formed  during  the  fermentation  is  carefully  saved  on  account  of  its 
containing  considerable  iodine.  The  results  of  this  process  are  very 
satisfactory.  The  lixiviation  of  iodine  from  the  kelp  is  double.  First, 
chlorides  and  iodides  are  extracted  by  cold  water,  then  potassium  sul- 
phate by  hot  water.  From  the  solution  containing  the  iodides,  iodine 
is  precipitated  by  potassium  chlorate,  which  separates  it  from  small 
quantities  of  bromides.  Before  the  end  of  the  competition  with  Peru, 
it  is  said  that  vessels  were  sent  out  to  collect  seaweed  for  this  purpose 
at  times  when  the  coast  was  bare.  In  March,  1877,  a  combination  was 
effected  between  the  European  and  South  American  producers,  and  the 
price  set  at  10J  pence  per  ounce.  This  combination  was  of  especial  value 
to  the  South  American  producers.  It  enabled  them  to  erect  new  works 
and  gave  an  impetus  to  the  trade  which  continued  even  after  the  com- 
bination was  broken  in  1880.  The  price  then  fell  to  less  than  half,  and 
with  continued  competition  had  reached  by  November,  1884,  3J  pence 
per  ounce,  the  same  price  which  ruled  in  1841,  before  iodine  entered  into 
chemical  manufactures.  It  was  predicted  in  November  that  a  combina- 
tion would  be  formed  and  the  price  then  go  to  9  pence  per  ounce.  The 
prediction  was  fulfilled. 

The  yield  from  South  American  deposits  has  been  estimated  as 
follows : 


Years. 

Pounds. 

1873  ... 

30  000 

1874 

100  000 

1875  

alOO  000 

1876 

110  000 

1877  

200  000 

1878 

280  000 

1879  

350,  000 

1880 

380  000 

1881  

200,  000 

1882' 

<  680,  000 

1883 

1   C32,  000 
C  6124,544 

I  c30,  000 

a  From  131  manufactories.       6  Chili.       c  Pern. 


The  processes  have  been  markedly  improved  both  in  the  methods 
and  arrangement  of  the  plant.  The  plant  at  Peruaua,  province  of 
Tarapaca  (formerly  in  Peru),  erected  in  1881,  cost  $20,000,  and  yields 


858 


MINERAL    RESOURCES. 


3,200  pounds  of  iodine  each  month.  The  sodium  nitrate  at  this  place 
contains  sodium  ioaate,  which  according  to  the  Gtinie  Civil,  1884,  may 
in  extreme  cases  amount  to  50  per  cent.  The  average  mother  liquor 
contains : 


Per  cent. 

Sodium  nitrate  

28 

Sodium  chloride 

11 

Sodium  sulphate   

3 

Magnesium  sulphate 

3 

Sodium  iodate    

*     22 

"Water 

33 

100 

As  the  iodine  is  present  largely  as  sodium  iodate,  it  is  precipitated  by 
the  old  method  of  sodium  acid  sulphite.  Very  new  and  economical 
methods  are  used  for  preparing  this  substance,  in  regard  to  which  full 
plans  are  given  in  Dingler's  Polytechnische  Journal,  Vol.  255,  page  299. 
In  Chili  much  of  the  iodine  occurs  as  sodium  iodide,  and  is  exported  as 
cuprous  iodide ;  117,330  pounds  of  this  substance  were  exported  in  1883. 

Imports. — The  following  table  shows  the  imports  of  iodine  into  the 
United  States  from  1867  to  1884  inclusive.  The  principal  use  of  iodine 
in  this  country  is  for  making  alcoholic  tincture  and  iodine  salts,  princi- 
pally potassium  iodide. 

Iodine  imported  and  entered  for  consumption  in  the  United  States,  1867  to  1884  inclusive. 


Fiscal  years  ending  June 
30— 

Crude. 

Eesublimed. 

Iodine 
salts. 

Total 

Quantity. 

Value. 

Quantity. 

Value. 

1867  

Pounds. 
12,  347 
18,  994 
17,  241 
27,  825 
74,320 
81,  437 
48,  991 
23,  861 
26,  058 
24,  913 
50,  123 
73,  687 
31,  779 
104,  703 
162,  863 
.      119,  952 
140,  642 
153,  550 

$28,  013 
55,  869 
50,  625 
70,  777 
212,  195 
292,  998 
206,  783 
89,  305 
74,  357 
55,  443 
111,  494 
230,  041 
122,  571 
501,  957 
336,  998 
213,311 
162,  036 
173,  251 

Pounds. 
3,199 
5,527 
5,882 
2,233 
956 
258 
10 
2 
54 

$6,764 
16,  178 
18,  356 
6,251 
3,  499 
2,166 
87 
16 
171 

$34,  777 
72,  047 
72,  570 
77,  028 
215,  694 
295,  205 
206,  870 
89,  321 
74,  531 
55,443 
111,494 
230,  053 
122,  571 
501,  969 
337,  676 
214,  605 
168,  016 
173,  744 

1868 

1869  

$3,  589 

1870 

1871  

41 

1872 

1873  

1874  

1875 

3 

1876  .... 

1877  

1878  

12 

1879  

1880  

2 
13 
15 
5 
336 

12 
30 
28 
8 
493 

1881 

648 
1,266 
5,972 
(a) 

1882  

1883 

1884 

a  Not  specified. 


